Gamin Yoon is an unassuming high schooler with clean-cut dark hair, round glasses, and a neat uniform that masks his highly athletic, well-toned build. Personality-wise, he is a deeply polite, fiercely loyal, and incredibly hard-working student who relies on his elite martial arts skills to protect his friends while pursuing his dream of going to college.

Sehyun Kim is a highly intelligent, studious, and fiercely loyal teenager with sharp, spiky brown hair who initially hides behind a blunt, cautious demeanor due to intense academic pressures before offering his elite brains to the Yusung Study Group.

Jiwoo Lee is a pretty, slender girl immediately recognizable by her short black hair, matching eyes, and school uniform. Personality-wise, she is a loud, outspoken, and fiercely loyal tomboy who hates injustice and uses her elite MMA and Judo skills to protect her friends.

Heewon Choi is a beautiful, cute high school girl with long, flowing reddish-brown hair and warm, expressive eyes. Personality-wise, she is an incredibly gentle, sweet, and timid person who, despite having no fighting skills, fiercely supports her friends with her quiet charm and kindness.

Jun Lee is a main supporting character in the webtoon Study Group, immediately recognizable by his short, vibrant scarlet hair and short, matching eyebrows. Personality-wise, he is a lively, enthusiastic, and highly supportive friend who loves giving dramatic names to fighting moves and uses his elite, leg-specialized combat skills to protect the Yusung Study Group.

Geonyeob Park is a sharp, handsome teenager with short dark hair who initially masks his deep emotional trauma with a friendly, innocent smile, hiding a deeply vengeful, antihero personality driven by the tragic loss of his mother.

Hankyeong Lee (commonly known as Miss Lee) is a very attractive young woman with long, wavy light brown hair and a hime-cut fringe who masks her inner fears with unparalleled optimism, unselfish kindness, and an unshakeable, tenacious determination to guide her delinquent students onto the right path.

is a major supporting character in Study Group who sports short, vibrant blonde or bleached hair and a standard high school uniform. Personality-wise, he is a fiercely protective, self-sacrificing, and determined brother who initially puts up a rough, delinquent-like facade

tall, handsome teenager with striking silver hair who hides a cold, calculating, and ruthless mob-heir personality behind his sophisticated looks.

Minhwan Ma is a handsome, dark-blue-haired teenager with a playboy look who acts as a cunning, cocky, and unpredictable criminal